Embodiments of the present invention generally relate to telecommunications and more specifically to techniques for forking media traffic to a processor for analysis.
Session border controllers (SBCs) or IP-to-IP gateways are being deployed by service providers to connect various networks running various voice-over IP (VoIP) protocols, such as H.323 and session initiation protocol (SIP). The SBC terminates and re-originates both signaling and media traffic for a VoIP communication between two devices. The media traffic is passed through the SBC as it is communicated from one device to the other. When a media packet arrives at the input of the SBC from a first device, a library, such as a real-time transport (RTP) library, updates the packet header with the SBC's IP address and port number. The packet is then forwarded to a second device. If real-time control protocol (RTCP) is used, the SBC overwrites the address imported with the packet with its own. By adding or overwriting the address and port, this causes any media returned from the second device to be received at the SBC, and not the first device. The processing performed by the SBC is intended to be minimal and add no substantial delay to the packet being sent. SBCs conventionally do not include a DSP, which may be used to generate media statistics. Thus, media statistics are not available for the media traffic.
A digital signal processor (DSP) may be inserted into the media traffic for the communication and generates media statistics. This involves media going through coding and decoding twice. The first time is for converting the media packets into a voice stream and the second time for converting the voice stream back into packets. This causes delay as the media has to go through two DSPs or two DSP channels connected back to back to have statistics generated on the voice stream. The delay introduced by the DSP affects the performance of the communication. Further, the delay is not desirable in a voice call or any other real-time communication because any delay affects the voice quality.